Reliability and validity of the Japanese version of the Yale-Brown Obsessive-Compulsive Scale

The reliability and validity of the Japanese version of the Yale-Brown Obsessive-Compulsive Scale (JY-BOCS) were determined by 20 raters for 12 Japanese patients with obsessive compulsive disorder at four institutions. Interrater reliability for the total JY-BOCS score was excellent, and the intraclass correlation coefficient was high (ICC = 0.960). Internal consistency was also excellent (Cronbach's alpha = 0.889). Concurrent and discriminant validity of the JY-BOCS was examined by comparing the scores on the JY-BOCS with those on the Maudsley Obsessional Compulsive Inventory (MOCI) and scales for depression and anxiety. A slight correlation was found between scores on the JY-BOCS and MOCI, but no significant correlations were found between scores on the JY-BOCS and those on scales for depression or anxiety.